Patents Assigned to Yumi Tsukuni
  • Pencil sharpener
    Patent number: 4506716
    Abstract: A pencil sharpener comprises a tapered pencil-insertion cutting blade. The said blade and/or pencil-insertion bore is disposed so that a taper angle of said blade on the rear side of said sharpener with respect to an axis of a pencil may be smaller than a taper angle of said bore, and so that an end portion of said blade on the rear side of said sharpener may be sited at a distance from a cut surface of the pencil in a direction of the rear side of said sharpener.
    Type: Grant
    Filed: October 25, 1982
    Date of Patent: March 26, 1985
    Assignee: Yumi Tsukuni
    Inventor: Hirro Hayashi